Isoflavonoids are an interesting group of compounds: they are produced mostly by legumes in response to plant stress, but have also shown potential in combating hormone-dependent cancers, cardiovascular disease, osteoporosis, and menopausal symptoms. Engineering isoflavonoid biosynthesis in plants can thus provide a good source of these compounds, for plant-based dietary supplements, and for providing plants extra defense mechanisms.

Bettina E. Deavours and Richard A. Dixon of the Samuel Roberts Noble Foundation set out to perform “Metabolic Engineering of Isoflavonoid Biosynthesis in Alfalfa.” They engineered alfalfa leaves to produce genistein glucoside without affecting regular plant growth or the expression of other alfalfa genes. Their findings appear in the latest issue of the Plant Physiology journal.

Using the IFS gene from the model legume Medicago truncatula, or the barrel medic, researchers successfully generated transgenic alfalfa producing, among other isoflavonoids, genistein. Since genistein is not normally synthesized in alfalfa leaves, scientists used microarrays to track if its accumulation caused any unexpected effects on gene expression. Tests showed, however, that gene expression carried on as usual.

Plant Physiology subscribers can read more by accessing the full article at http://www.plantphysiol.org/cgi/
reprint/138/4/2245.

Other readers can view the abstract at http://www.plantphysiol.org/cgi/content/abstract/138/4/2245.